Radium-226, measurement Sensitivity

Whether in the environment or in the human body, uranium will undergo radioactive decay to form a series of radioactive nuclides that end in a stable isotope of lead (see Chapter 3). Examples of these include radioactive isotopes of the elements thorium, radium, radon, polonium, and lead. Analytical methods with the required sensitivity and accuracy are also available for quantification of these elements in the environment where large sample are normally available (EPA 1980,1984), but not necessarily for the levels from the decay of uranium in the body. More sensitive analytical methods are needed for accurately measuring very low levels of these radionuclides. 

Whole-body counters were originally developed for investigation of poisoning by radioactive substances such as radium. They are now used diagnostically and consist of a large scintillation, or semiconductor, detector with the whole system, including the patient, placed in a heavily shielded room. The sensitivity is sufficient to measure natural radioactivity in the human body from such nuclides as... 

D. Coster, and 0. Stelhng studied the X-ray spectrum and D. M. Yost, the absorption of X-rays. I. PlotnikofE and M. Karshulin measured the absorption spectrum and the region of photochemical sensitivity for soln. of potassium chromate in colloidion films—with methyl alcohol as acceptor. A. Kailan found that an aq. soln. of potassium chromate is reduced by radium rays more slowly than potassium dichromate. E. Montignie observed that after exposure to ultra-violet light, potassium chromate affects a photographic plate. 

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